In recent years, with the rapid development of electronics and communication technologies, development of camera technologies, and spread of smartphones, an amount of collected video data has been rapidly increased, and an amount of information generated into multimedia data such as image data, video data, and voice data has also been increased tremendously.
In reproducing stored information as a video, conventionally, when searching for recorded content after recording is finished using a video-recording camera, recorded videos are sequentially played back, which requires a long time and concentration of the user. In order to prevent such a problem and to reduce the searching time, there is a method of searching using a fast forwarding method. However, since the digital recording method shows a video without instantaneous frames, there are problems in that a recorded object is missed or the video is not natural. Particularly, in the case of a surveillance video such as closed circuit television (CCTV), a large effort is required for the user because it is necessary to watch a video, which has not been recorded for observation purpose, for a long period of time.
As a result, in most surveillance systems nowadays, a person directly observes a video to search for a target object without intelligent analysis of surveillance video. This process requires a very long time and causes extreme fatigue of an observer. Also, when the user plays a video at a higher speed or skips scenes in videos to reduce the searching time, there is a problem in that a risk of missing a target object is high.